History of Tuorla Observatory

Yrjö Väisälä(1891-1971)

In 1923, Yrjö Väisälä became professor of physics at
the newly founded University of Turku, assuming in 1927 responsibilities for
astronomy, and in the 1950's founded Tuorla Observatory. In
many ways Väisälä can be thought of as the father of space
research in Finland. Väisälä was truly forward thinking in the
use of space for scientific research. He proposed in 1946, at a meeting of
the Academy of Finland, the use of
rockets or balloons with on-board flashes so that geodetic triangulation
could be made even between the continents, and suggested that artificial
satellites would be even better. The next year he was already doing
experiments with small rockets, and giving interviews explaining how
artificial satellites could be used to explore the solar system, and beyond!

On 17 April 1950 the caretakers of the Tuorla Manor House consented to the
request by Yrjö Väisälä to move the observatory of the
university from Iso-Heikkilä to Laukkavuori in Tuorla. In 1951
Väisälä completed his detailed plans of the observatory
including meterological and optical instruments. The observatory was
officially founded on 29 April 1952. The 71 metre long optical tunnel was
built between 11 February 1952 and 31 May 1952. During 1953 a vertical tunnel
was built inside a concrete pillar, which was 27 metres from the bottom of
the tunnel or 15 metres from groundlevel, and 6 metres in diameter. It took
a further 7 years, before the concrete pillar was completed with a dome on top
of it. The older section of the present observatory building was completed in
1957. Research activities during the leadership of Väisälä
included setting up the geodetic triangulation network for measuring
distances, optical work, Zenith telescope studies of polar motion, detections
and orbital calculations of minor planets and comets. Professor, Academician
Väisälä was the director of the observatory until his death
on 21 July 1971.

Väisälä was a superb optician, using the tunnel under the
hill at Tuorla Observatory, from which interference
measurements defining the length standard for geodesy were made and later
adopted internationally. The highest quality optics were produced,
Väisälä being one of the few in the world who could produce
the demanding corrector glasses for Schmidt telescopes. Väisälä
actually thought of the Schmidt-type telescope several years before Schmidt,
and included the design in his lecture notes on optics, but thought the idea
so obvious he didn't publish it further! Väisälä, together with
Liisi Oterma, who later became professor at Tuorla, discovered more minor
planets in their most effective years than all the other observatories in the
world put together.

Prof. Liisi Oterma became director of the observatory after
Väisälä. In 1971 a new 60cm reflector was erected. During the
1974 nationalisation of the Turku University, the observatory lost its
independent status and became part of the Department of Physical Sciences.

Prof. Vilppu Piirola was the director of the observatory in 1978-80.
Piirola broadened the research activities of the observatory with polarised
stellar systems.

Prof. Mauri Valtonen became the director of the observatory in 1980. The
scope of the research was vastly broadened as active galaxies became a
significant field at the observatory. Stellar dynamics and optics stayed as
vital field of research. In 1989 the Observatory buildings were enlarged,
and in 1991 Tuorla became once again an independent research institute under
the direct jurisdiction of the university. In 1990-1995 and 2000-2001
Valtonen was on leave from directorship of the observatory, during which
time Professors Pekka Teerikorpi, Seppo Mikkola and Chris Flynn took up the
directorship. In 1995 the Tuorla staff member Vilppu Piirola was appointed
to the directorship of the Nordic Optical
Telescope, serving through till 2002.

Prof. Esko Valtaoja took over the reigns from Mauri Valtonen in 2002;
much of the research is now part of a push into space-based astronomy and
astrophysics; Valtaoja's appointment was as a new chair in space-based
astronomy. Yet another new building was added to the hill, containing 12
new offices and 2 flats for visitors and observers; a millimetre Solar radio
telescope was installed and commissioned. In 2002 Tuorla Observatory
turned 50!

This page was last modified by
Rami Rekola
on
19/02/2009 14:55
astroweb@utu.fi